1. Field of the Invention
The present invention generally relates to a dental attachment or anchoring structure for attaching a removable dental appliance such as a full denture, overdenture, partial denture, or the like to a remaining non-vital root, an adjacent tooth, or to an endosseous implant.
2. Related Art
There are many different types of dental attachments for releasably anchoring a dental appliance to one or more roots or implants, or to an adjacent tooth. In many cases, the attachments comprise mating, snap engageable male and female parts, one of which is attached to the denture and the other of which is attached to a root, implant, or adjacent tooth. One known attachment has a first part which is pivotally engaged in a cap secured in an implant, and a second part secured to an implant, root, or the like. Some attachments of this general type are described in U.S. Pat. Nos. 5,417,570, 6,030,219, and 6,299,447, for example.
Another known attachment uses an O-ring which engages over a ball at the end of an implant abutment or post. In one example, the O-ring engages in a retainer which is attached to a denture. One problem with O-ring or similar resilient ring attachments is that they work best when perfectly straight. Any angulation of the abutment will cause wear and roll-out of the ring due to uneven biting forces.